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依据水面红外发射和红外遥感测温原理,采用HDG-高灵敏度红外测温仪和常规测量仪器相结合的方法,在实验室空气稳定条件下,模拟测得了水面皮层破坏-复原(重建)的热力过程和气-水温差对水面皮层复原过程的影响,获得了大量的测量数据。数据分析表明,当气-水温差从3.0℃变为11.5℃时,水面皮层破坏可导致皮温增量从气-水温差3.0℃时的0.15℃变到11.5℃时的0.45℃,并发现恢复时间与气-水温差呈负线性关系。  相似文献   
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The recent sea-ice reduction in the Arctic Ocean is not spatially uniform, but is disproportionally large around the Northwind Ridge and Chukchi Plateau compared to elsewhere in the Canada Basin. In the Northwind Ridge region, Pacific Summer Water (PSW) delivered from the Bering Sea occupies the subsurface layer. The spatial distribution of warm PSW shows a quite similar pattern to the recent ice retreat, suggesting the influence of PSW on the sea-ice reduction. To understand the regionality of the recent ice retreat, we examine the dynamics and timing of the delivery of the PSW into this region. Here, we adopt a two-layer linearized potential vorticity equation to investigate the behavior of Rossby waves in the presence of a topographic discontinuity in the high latitude ocean. The analytical results show a quite different structure from those of mid-latitude basins due to the small value of β. Incident barotropic waves excited by the sea-ice motion with large annual variation can be scattered into both barotropic and baroclinic modes at the discontinuity. Since the scattered baroclinic Rossby wave with annual frequency cannot propagate freely, a strong baroclinic current near the topographic discontinuity is established. The seasonal variation of current near the topographic discontinuity would cause a kind of selective switching system for shelf water transport into the basin. In our simple analytical model, the enhanced northward transport of summer water and reduced northward transport of winter water are well demonstrated. The present study indicates that these basic dynamics imply that a strengthening of the surface forcing during winter in the Canada Basin could cause sea-ice reduction in the Western Arctic through the changes of underlying Pacific Summer Water.  相似文献   
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根据1998年和2000年东海北部的营养盐调查资料和相应的历史资料,以及同期开展的虾类资源调查资料,研究了冬、夏季长江冲淡水的流向以及它对长江口渔场、舟山渔场硅酸盐分布规律和虾类生物量分布规律的影响。结果表明,长江冲淡水转向的原因可以归纳为4类,夏季长江冲淡水的流动界限由123°E,30.3°N到127.3°E,33°N的直线和由123°E,31.8°N到127.3°E,34.5°N的直线所围的区域。长江冲淡水给长江口渔场、舟山渔场提供了大量的硅酸盐,对提高该海区的初级生产力起到了积极的作用,有利于生物的繁衍生息,提高了生物量。最后,用该海区虾类的分布密度证实了由该水团所做出的对生物量的推论。  相似文献   
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Hydrographic properties from CTD and discrete bottle sample profiles covering the Japan (East) Sea in summer, 1999, are presented in vertical sections, maps at standard depths, maps on isopycnal surfaces, and as property–property distributions. This data set covers most of the Sea with the exception of the western boundary region and northern Tatar Strait, and includes nutrients, pH, alkalinity, and chlorofluorocarbons, as well as the usual temperature, salinity, and oxygen observations.  相似文献   
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A preliminary optical classification of lakes in Estonia and south Finland which can also be used for small bays of the Baltic Sea is elaborated. The classification is based on the optical properties of water (diffuse attenuation coefficient, diffuse reflectance) and parameters that are routinely monitored in water bodies (Secchi depth, concentration of chlorophyll-a, total suspended matter and yellow substance). The data complex used for our classification covers different types of water ecosystems (ranging from oligotrophic to hypertrophic) and the variability of water constituent concentrations in the ice-free period in Estonia and south Finland. Using cluster analysis, we found 5 optical classes of waters: clear (C), moderate (M), turbid (T), very turbid (V) and brown (B). There is satisfactory correspondence between class of water, shape of diffuse attenuation coefficient and diffuse reflectance spectra and trophic state of the lakes.  相似文献   
60.
Since the Intermediate Oyashio Water (IOW) gradually accumulates in Sagami Bay, it can reasonably be supposed that the IOW also flows out from Sagami Bay, even though it may be altered by mixing with other waters. We have occasionally observed a water less than 34.2 psu with a potential density of 26.8 at the southeastern area off Izu Peninsula in July 1993 by the training vessel Seisui-maru of Mie University. Observational data supplied by the Japan Meteorological Agency and the Kanagawa Prefectural Fisheries Experimental Station show that the IOW of less than 34.1 psu was observed at northern stations of the line PT (KJ) off the Boso Peninsula and to the east of Oshima in the late spring 1993. Based upon these observations, it is concluded that the IOW flows out from Sagami Bay into the Shikoku Basin along southeastern area off the Izu Peninsula. The less saline water (<34.2 psu) was also observed to the west of Miyake-jima during the same cruise, and the westward intrusion of IOW from south of the Boso Peninsula to the Shikoku Basin through the gate area of the Kuroshio path over the Izu Ridge was detected. This event indicated that the IOW branched south of the Boso Peninsula and flowed into Sagami Bay and/or into the gate area over the Izu Ridge. The southward intrusion of IOW into the south of the Boso Peninsula is discussed in relation to the latitudinal location of the main axes of the Kuroshio and the Oyashio. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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